Electric lamp socket with pin tap connecting means



Nov. 22, 1955 F. D. KEELER ETAL 2,724,810

ELECTRIC LAMP SOCKET WITH PIN TAP CONNECTING MEANS Filed Sept. 18,1952

a: I ";I:== iill v llll NCLYC ODM Wm United States Patent ELECTRIC LAMP SOCKET WITH PIN TAP CONNECTING MEANS Frederick D. Keeler, Trumbull, Conn., and Mario DAngelo, West Hempstead, N. Y., assignors to Gilbert Manufacturing Co., Inc., Long'lsland City, N. Y., a corporation of New York Application September 18, 1952, Serial No. 310,188

4 Claims. (Cl. 339-99) This invention relates to improvements in electric sockets for lamp bulbs or the like, and in particular to modifications of conventional electric sockets permitting greatly simplified constructions, assembly and connection to a two-conductor electric cord.

In the connection of conventional electric sockets to conductor cords, as in the case of lamps or the like, it has heretofore been necessary to cut, strip and twist the wires of the cord, then disassemble the socket, and use a screw driver on its binding posts to connect the wires thereto. According to the present invention, the greater part of this procedure is completely eliminated, particularly the stripping, twisting and connecting of the wires.

tions 11 generally placed along the lower edge thereof for Instead, the cord need merely be cut to size, laid into a v cord-receiving channel over which a cover is slid. These few steps complete the assembly and connection of the wires to the socket. At the same time, the fabrication of the socket and its parts is greatly simplified, by a novel and improved design permitting use of the rapid and inexpensive stamping and molding processes, and minimizing assembly operations.

It is accordingly an important object of the instant invention to provide an improved electric socket capable of rapid assembly with ordinary 2-conductor electric wires.

It is a further object of the invention to provide an improved electric socket which eliminates the usual screw connectors for the connecting wires.

It is another object of the invention to provide an improved electric socket which reduces to a minimum the number of parts and assembly operations required and which permits the use of inexpensive and easily fabricated parts.

Yet another object of the present invention is to pro-v vide an electric socket construction in which connection to a conductor cord may be readily made without requiring any particular mechanical skill or tools, or separation or stripping of the cord conductors.

Other objects and advantages of the invention-will in part be obvious and in part appear hereinafter.

The invention in its preferred form is embodied in an electric socket of essentially conventional exterior construction, the electrical contacts within the socket being mounted on an insulating base and'having integral wireinsulation-piercing prongs reaching into and insulating channel adapted to receive the two-wire conductor and cooperating with a cover adapted to press the conductor in place to make contact with the prongs, without the use of screws or tools.

In the drawing,

Figure 1 is an exploded perspective view of a preferred form of an electric socket assembly made in accordance with the instant invention; i

Figure 2 is a plan view of the socket base with the casing and sliding cover removed;

Figure 3 is a longitudinal sectional view of the device of Figure 1, omitting the casing;

locking engagement with similar corrugations on the inner surface of cap 12.

In the side of the socket shell 10 a notch or keyway 13 is provided for locking the interior parts against rotation, as described below. Within the socket shell 10 is placed a conventional insulating lining 14, having an opening 15 corresponding to notch 13. Lining 14 surrounds the threaded metallic contact shell 16 which receives the base of the electric light bulb when screwed into the socket.

Fastened to the contact shell 16, in a manner to be described, is an insulating plate 17 having projections or keys 18 on diametrically opposite sides thereof. These projections 18 are fashioned to fit into notches 13 and 15 for preventing rotation between the casing shell 10 and the remaining structure.

Mounted on the plate 17 in the manner to be described is a cord-connecting member 20. Member 20, as shown most clearly in Figure '1, has a longitudinal channel 25 extending therealong. The interior of member 20 is generally hollow, except for two pairs of partitions 26, 27 which define narrow passages running perpendicularly to channel 25.

.The base 28 of member 20 is apertured or slotted in line with these passages, and respective contact elements 29 and 30 are positioned within these passages and extend through the base apertures.

Contact element 29 is shown in Fig. 5, as it is formed prior to assembly, and is preferably fabricated by stamping from conductive sheet metal. It is formed with a sharp pointed prong or prongs 31 at one end, at which a locating or positioning tab32 is formed by bendingover a flap of the material. A strengthening rib or ribs 33 is formed partially along the length of element 29. A hole or slot 34 is formed at the opposite end of the contact element 29. p

The other contact element 30 is shown in Fig. 6, before assembly, and has similar pointed prongs 34 locating tab 35, strengthening rib 36 and apertured end 37. Element 30 differs from element 29 only in length and if desired, in the use of an aperture 37 rather than a slot 34. v

In assembling the socket, the cord connecting member 20 is placed centrally upon plate 17, and contact element 29 is inserted through the passage between partitions 27, through the aperture in base 28 of member 2!), and through an aperture 39 in plate 17. Then the end 4 of contact 29 is bent outwardly, so that the slot 34 is in registry with an opening 41 in plate 17 which is also aligned with an opening in base 28 of member 20. The end portion 38 of contact shell 16 has an opening 43 which is aligned with the aperture just referred to. A rivet 42 then secures member 20, plate 17, element 29 and contact shell 16 together, and electrically connects contact element 29 to contact shell 16. The other end portion 44 of shell 16 is secured to plate 16 and member 20 by a similar rivet. 39. Then the contact element 30 is inserted into the passage between partitions 26 and through .an aligned opening in plate 17 into the interior of shell 16, where its end portion 45 is bent toward the axis of shell 16 to form a contact for the center base terminal of the electric light bulb.

In thus assembling the socket parts, it will be noted that the prongs 31 of contact element 29 are adjacent one wall of channel 25 while the prongs 34 of the other element 30 are adjacent the other channel wall. As a consequence, when a conventional twin-conductor rubber covered cord or similar cord is laid into channel 25, the prongs 31 and 34 are aligned to contact the respective wires of the cord, upon pressing the cord upon these prongs to cause the prongs to pierce the cord insulation. For the purpose of making this connection, the side walls of the member 24 are turned outwardly at their upper edges to form lips 21, 22, which engage a mating cover piece 23.

To connect the cord 51 to the socket, it is merely necessary to lay either the end or an intermediate portion of the cord 51 in the channel 25 and then to slide the cover piece 23 in place, which presses the cord 51 upon the prongs 31 and 34 extending into channel 25, so that the prongs make electrical contact with the respective wires within the cord. Then the cap 12 is assembled to the casing shell to complete the socket with the cord 51 passing through the central aperture in cap 12. It will thus be seen that the connector member 20, the plate 17 and the contact shell 16 form a unitary structure. Upon slipping on the lining 14 and easing shell 10, the projections 17 engage the notches to prevent relative rotation between the casing and the interior parts.

It will thus be apparent that both the assembly of the socket and the connection of the wire thereto are extremely simplified and made relatively inexpensive.

It will be understood that many equivalent constructions are possible. Thus, the plate 15 may be formed integrally with the connector member 20, and both may be modified in shape for convenience of molding and minimum size.

Alternatively, plate 15 may be omitted, and the base of member provided with rotation-preventing means equivalent to projections 17. Any other rotation-preventing means may be used as desired. Instead of rivets 39, 42, any functionally equivalent fastening means may be used.

The above description should be considered illustrative only, and not to be interpreted in a limiting sense, the present invention being limited solely as defined in the appended claims.

What is claimed is:

l. A socket for electric light bulbs comprising a conductive casing having relatively separable cap and shell portions, said cap having an axial cord-receiving aperture, an insulating lining within said casing, said shell portion and said lining having aligned cut-out portions in oppositely disposed sections thereof, and a socket structure within said lining, said socket structure comprising an insulating body having a pair of parallel apertures extending therealong axially of said socket and a conductorcord-receiving channel at one end of said structure extending completely through said structure across the ends of said apertures in a direction connecting said aperture ends, an insulating plate having a pair of projections adapted to engage said shell and lining cut-out portions and fixed to said insulating body at the other end thereof, said plate having apertures in registry with said insulating body apertures, an integral electrical contact member within each of said aligned insulating body and insulating plate apertures and having an insulation-piercing pointed end extending within said conductor-cord-receiving channel, the pointed ends of said two contact members being respectively adjacent opposite sides of said channel and spaced along the length of said channel, one of said contact members having the other end thereof bent integrally to form a tongue extending over the axis of said socket to form a contact for the center base terminal of a thread-type electric light bulb, a metallic thread-bearing contact shell fixed to said insulating body and insulating plate and surrounding said contact tongue, said contact shell being electrically connected to the other end of said other contact member, said channel being formed with a pair of parallel outwardly-extending lips and a cover piece having a T-shaped channel therein slidably engaging said lips for pressing a conductor cord on said pointed ends to pierce the insulation of said conductor cord to contact the wires thereof and to provide electrical connection between the wires of said cord and said contact shell and tongue whereby connection may be made between said wires and a thread-type electric light bulb screwed into said contact shell.

2. A socket for electric light bulbs, comprising a casing having relatively separable cap and shell portions, an insulating lining within said casing, and a socket structure within said lining and having means cooperative with said casing shell portion to prevent relative rotation thereof, said socket structure comprising an insulating body having a pair of parallel apertures extending therealong axially of said socket and a conductor-cord-receiving channel at one end extending through said body across the ends of said apertures in a direction connecting said ends, an electrical contact member within each of said apertures and having an insulation-piercing pointed end extending Within said channel, the pointed ends of said two contact members being respectively adjacent opposite sides of said channel and spaced along the length of said channel, one of said contact members having the other end thereof bent to form an integral tongue extending over the axis of said socket to form a contact for the center base terminal of a thread-type electric light bulb, a metallic threaded contact shell fixed to said insulating body and surrounding said tongue, said contact shell being electrically connected to the other end of said other contact member, said channel being formed with a pair of parallel outwardly extending lips, and a cover piece having a T-shaped channel slidably engaging said lips for pressing a conductor cord on said contact member pointed ends to provide electrical connection between the wires of said cord and said contact shell and tongue, whereby connection may be made between said wires and a thread-type electric light bulb screwed into said contact shell.

3. A socket for electric light bulbs, comprising an insulating body having a pair of parallel apertures extending therethrough axially of said socket and a conductor-cordreceiving channel at one end extending through said body and across the ends of said apertures in the direction conmeeting said aperture end, an electrical contact member Within each of said apertures and having an insulationpiercing pointed end extending within said channel, the pointed ends of said two contact members being respectively adjacent opposite sides of and spaced along said channel, one of said contact members having the other end thereof bent to form an integral tongue extending over the axis of said socket to form a contact for the center base terminal of a thread-type electric light bulb, a metallic threaded contact shell fixed to said insulating body and surrounding said tongue, said contact shell being electrically connected to the other end of said other contact member, said channel being formed with a pair of parallel outwardly extending lips, and a cover piece with a substantially T-shaped channel slidably engaging said lips for pressing a conductor cord on said contact member pointed ends to provide electrical connection between the wires of said cord and said contact shell and tongue, whereby connection may be made between said wires and a threadtype electric light bulb screwed into said contact shell.

4. A socket for electric light bulbs, comprising an insulating structure having a pair of parallel apertures extending therethrough and a conductor-cord-receiving channel extending across the ends of said apertures in a direction from one aperture to the other, an electrical contact member within each of said apertures and having an insulation-piercing pointed end extending within said channel, the pointed ends of said two contact memlg... W

bers being respectively adjacent opposite sides of said channel and being spaced along the length of said channel, one of said contact members having a center socket terminal formed integrally therewith at the other end thereof,

a metallic threaded contact shell fixed to said insulating 5 between said wires and said contact shell and center terminal whereby connection may be made between said wires and a thread-type electric light bulb screwed into said contact shell.

References Cited in the file of this patent UNITED STATES PATENTS 1,013,681 Osland et a1. Jan. 2, 1912 1,247,026 Smith NOV. 20, 1917 1,643,790 Slade Sept. 27, 1927 2,559,706 Brooks July 10, 1951 2,647,246 Gilbert July 28, 1953 FOREIGN PATENTS 731,999 Germany Feb. 19, 1943 

